Severe headache and body spasms

Last year I had a number of incidents where I would start to feel really cold and my body would automatically start stretching, which I couldn't control. Like when you wake up and stretch. The headache would get worse and worse until I felt like vomiting and my teeth would chatter so badly I had to grab whatever was at reach to put between my teeth. All I could do was get into bed and wait for it to pass, usually 15 agonizing minutes.
Now it is happening again. I had one last night and then again tonight. I have a temperature and am freezing cold also.
Does anyone have any idea what this could be. I am on Subutex medication. A replacement for Methadone, and also Lovan anti-depressants.